sync local pi changes

.pi/agent/extensions/dev-tools/index.ts

@@ -0,0 +1,50 @@
+import type { ExtensionAPI } from "@mariozechner/pi-coding-agent";
+import { createCommandFormatterRunner } from "./src/formatting/command-runner.ts";
+import { createCommandDiagnosticsBackend } from "./src/diagnostics/command-backend.ts";
+import { createLspClientManager } from "./src/diagnostics/lsp-client.ts";
+import { createSetupSuggestTool } from "./src/tools/setup-suggest.ts";
+import { probeProject } from "./src/project-probe.ts";
+import { createFormattedWriteTool } from "./src/tools/write.ts";
+import { createFormattedEditTool } from "./src/tools/edit.ts";
+import { createDevToolsRuntime } from "./src/runtime.ts";
+
+export default function devTools(pi: ExtensionAPI) {
+  const cwd = process.cwd();
+  const agentDir = process.env.PI_CODING_AGENT_DIR ?? `${process.env.HOME}/.pi/agent`;
+
+  const runtime = createDevToolsRuntime({
+    cwd,
+    agentDir,
+    formatterRunner: createCommandFormatterRunner({
+      execCommand: async (command, args, options) => {
+        const result = await pi.exec(command, args, { timeout: options.timeout });
+        return { code: result.code ?? 0, stdout: result.stdout ?? "", stderr: result.stderr ?? "" };
+      },
+    }),
+    commandBackend: createCommandDiagnosticsBackend({
+      execCommand: async (command, args, options) => {
+        const result = await pi.exec(command, args, { timeout: options.timeout });
+        return { code: result.code ?? 0, stdout: result.stdout ?? "", stderr: result.stderr ?? "" };
+      },
+    }),
+    lspBackend: createLspClientManager(),
+    probeProject,
+  });
+
+  pi.registerTool(createFormattedEditTool(cwd, runtime));
+  pi.registerTool(createFormattedWriteTool(cwd, runtime));
+  pi.registerTool(createSetupSuggestTool({
+    suggestSetup: async () => {
+      const probe = await probeProject({ cwd });
+      return probe.summary;
+    },
+  }));
+
+  pi.on("before_agent_start", async (event) => {
+    const block = runtime.getPromptBlock();
+    if (!block) return;
+    return {
+      systemPrompt: `${event.systemPrompt}\n\n${block}`,
+    };
+  });
+}

.pi/agent/extensions/dev-tools/package.json

@@ -0,0 +1,23 @@
+{
+  "name": "pi-dev-tools-extension",
+  "private": true,
+  "version": "0.0.0",
+  "type": "module",
+  "scripts": {
+    "test": "tsx --test src/*.test.ts src/**/*.test.ts"
+  },
+  "pi": {
+    "extensions": ["./index.ts"]
+  },
+  "dependencies": {
+    "@sinclair/typebox": "^0.34.49",
+    "picomatch": "^4.0.2",
+    "vscode-jsonrpc": "^8.2.1"
+  },
+  "devDependencies": {
+    "@mariozechner/pi-coding-agent": "^0.66.1",
+    "@types/node": "^25.5.2",
+    "tsx": "^4.21.0",
+    "typescript": "^6.0.2"
+  }
+}

.pi/agent/extensions/dev-tools/src/config.test.ts

@@ -0,0 +1,37 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { mergeDevToolsConfig } from "./config.ts";
+
+test("mergeDevToolsConfig lets project defaults override global defaults and replace same-name profiles", () => {
+  const merged = mergeDevToolsConfig(
+    {
+      defaults: { formatTimeoutMs: 8000, maxDiagnosticsPerFile: 10 },
+      profiles: [
+        {
+          name: "typescript",
+          match: ["**/*.ts"],
+          workspaceRootMarkers: ["package.json"],
+          formatter: { kind: "command", command: ["prettier", "--write", "{file}"] },
+          diagnostics: [],
+        },
+      ],
+    },
+    {
+      defaults: { formatTimeoutMs: 3000 },
+      profiles: [
+        {
+          name: "typescript",
+          match: ["src/**/*.ts"],
+          workspaceRootMarkers: ["tsconfig.json"],
+          formatter: { kind: "command", command: ["biome", "format", "--write", "{file}"] },
+          diagnostics: [],
+        },
+      ],
+    },
+  );
+
+  assert.equal(merged.defaults.formatTimeoutMs, 3000);
+  assert.equal(merged.defaults.maxDiagnosticsPerFile, 10);
+  assert.deepEqual(merged.profiles.map((profile) => profile.name), ["typescript"]);
+  assert.deepEqual(merged.profiles[0]?.match, ["src/**/*.ts"]);
+});

.pi/agent/extensions/dev-tools/src/config.ts

@@ -0,0 +1,38 @@
+import { existsSync, readFileSync } from "node:fs";
+import { resolve } from "node:path";
+import { Value } from "@sinclair/typebox/value";
+import { DevToolsConfigSchema, type DevToolsConfig } from "./schema.ts";
+
+export function mergeDevToolsConfig(globalConfig?: DevToolsConfig, projectConfig?: DevToolsConfig): DevToolsConfig {
+  const defaults = {
+    ...(globalConfig?.defaults ?? {}),
+    ...(projectConfig?.defaults ?? {}),
+  };
+
+  const globalProfiles = new Map((globalConfig?.profiles ?? []).map((profile) => [profile.name, profile]));
+  const mergedProfiles = [...(projectConfig?.profiles ?? [])];
+
+  for (const profile of globalProfiles.values()) {
+    if (!mergedProfiles.some((candidate) => candidate.name === profile.name)) {
+      mergedProfiles.push(profile);
+    }
+  }
+
+  return { defaults, profiles: mergedProfiles };
+}
+
+function readConfigIfPresent(path: string): DevToolsConfig | undefined {
+  if (!existsSync(path)) return undefined;
+  const parsed = JSON.parse(readFileSync(path, "utf8"));
+  if (!Value.Check(DevToolsConfigSchema, parsed)) {
+    const [firstError] = [...Value.Errors(DevToolsConfigSchema, parsed)];
+    throw new Error(`Invalid dev-tools config at ${path}: ${firstError?.message ?? "validation failed"}`);
+  }
+  return parsed as DevToolsConfig;
+}
+
+export function loadDevToolsConfig(cwd: string, agentDir: string): DevToolsConfig | undefined {
+  const globalPath = resolve(agentDir, "dev-tools.json");
+  const projectPath = resolve(cwd, ".pi/dev-tools.json");
+  return mergeDevToolsConfig(readConfigIfPresent(globalPath), readConfigIfPresent(projectPath));
+}

.pi/agent/extensions/dev-tools/src/diagnostics/command-backend.test.ts

@@ -0,0 +1,40 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { createCommandDiagnosticsBackend } from "./command-backend.ts";
+
+test("eslint-json parser returns normalized diagnostics", async () => {
+  const backend = createCommandDiagnosticsBackend({
+    execCommand: async () => ({
+      code: 1,
+      stdout: JSON.stringify([
+        {
+          filePath: "/repo/src/app.ts",
+          messages: [
+            {
+              ruleId: "no-console",
+              severity: 2,
+              message: "Unexpected console statement.",
+              line: 2,
+              column: 3,
+            },
+          ],
+        },
+      ]),
+      stderr: "",
+    }),
+  });
+
+  const result = await backend.collect({
+    absolutePath: "/repo/src/app.ts",
+    workspaceRoot: "/repo",
+    backend: {
+      kind: "command",
+      parser: "eslint-json",
+      command: ["eslint", "--format", "json", "{file}"],
+    },
+  });
+
+  assert.equal(result.status, "ok");
+  assert.equal(result.items[0]?.severity, "error");
+  assert.equal(result.items[0]?.message, "Unexpected console statement.");
+});

.pi/agent/extensions/dev-tools/src/diagnostics/command-backend.ts

@@ -0,0 +1,45 @@
+import type { DiagnosticsConfig } from "../schema.ts";
+import type { DiagnosticsState, NormalizedDiagnostic } from "./types.ts";
+
+function parseEslintJson(stdout: string): NormalizedDiagnostic[] {
+  const parsed = JSON.parse(stdout) as Array<any>;
+  return parsed.flatMap((entry) =>
+    (entry.messages ?? []).map((message: any) => ({
+      severity: message.severity === 2 ? "error" : "warning",
+      message: message.message,
+      line: message.line,
+      column: message.column,
+      source: "eslint",
+      code: message.ruleId ?? undefined,
+    })),
+  );
+}
+
+export function createCommandDiagnosticsBackend(deps: {
+  execCommand: (
+    command: string,
+    args: string[],
+    options: { cwd: string; timeout?: number },
+  ) => Promise<{ code: number; stdout: string; stderr: string }>;
+}) {
+  return {
+    async collect(input: {
+      absolutePath: string;
+      workspaceRoot: string;
+      backend: Extract<DiagnosticsConfig, { kind: "command" }>;
+      timeoutMs?: number;
+    }): Promise<DiagnosticsState> {
+      const [command, ...args] = input.backend.command.map((part) => part.replaceAll("{file}", input.absolutePath));
+      const result = await deps.execCommand(command, args, { cwd: input.workspaceRoot, timeout: input.timeoutMs });
+
+      try {
+        if (input.backend.parser === "eslint-json") {
+          return { status: "ok", items: parseEslintJson(result.stdout) };
+        }
+        return { status: "unavailable", items: [], message: `Unsupported diagnostics parser: ${input.backend.parser}` };
+      } catch (error) {
+        return { status: "unavailable", items: [], message: (error as Error).message };
+      }
+    },
+  };
+}

.pi/agent/extensions/dev-tools/src/diagnostics/lsp-client.test.ts

@@ -0,0 +1,41 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { createLspClientManager } from "./lsp-client.ts";
+
+test("collectForFile sends initialize + didOpen and resolves publishDiagnostics", async () => {
+  const notifications: Array<{ method: string; params: any }> = [];
+
+  const manager = createLspClientManager({
+    createConnection: async () => ({
+      async initialize() {},
+      async openTextDocument(params) {
+        notifications.push({ method: "textDocument/didOpen", params });
+      },
+      async collectDiagnostics() {
+        return [
+          {
+            severity: "error",
+            message: "Type 'number' is not assignable to type 'string'.",
+            line: 1,
+            column: 7,
+            source: "tsserver",
+          },
+        ];
+      },
+      async dispose() {},
+    }),
+  });
+
+  const result = await manager.collectForFile({
+    key: "typescript:/repo",
+    absolutePath: "/repo/src/app.ts",
+    workspaceRoot: "/repo",
+    languageId: "typescript",
+    text: "const x: string = 1\n",
+    command: ["typescript-language-server", "--stdio"],
+  });
+
+  assert.equal(result.status, "ok");
+  assert.equal(result.items[0]?.source, "tsserver");
+  assert.equal(notifications[0]?.method, "textDocument/didOpen");
+});

.pi/agent/extensions/dev-tools/src/diagnostics/lsp-client.ts

@@ -0,0 +1,102 @@
+import { spawn } from "node:child_process";
+import { pathToFileURL } from "node:url";
+import * as rpc from "vscode-jsonrpc/node";
+import type { DiagnosticsState } from "./types.ts";
+
+const INITIALIZE = new rpc.RequestType<any, any, void, void>("initialize");
+const DID_OPEN = new rpc.NotificationType<any, void>("textDocument/didOpen");
+const INITIALIZED = new rpc.NotificationType<any, void>("initialized");
+const PUBLISH_DIAGNOSTICS = new rpc.NotificationType<any, void>("textDocument/publishDiagnostics");
+
+type LspConnection = {
+  initialize(): Promise<void>;
+  openTextDocument(params: any): Promise<void>;
+  collectDiagnostics(): Promise<DiagnosticsState["items"]>;
+  dispose(): Promise<void>;
+};
+
+export function createLspClientManager(deps: {
+  createConnection?: (input: { workspaceRoot: string; command: string[] }) => Promise<LspConnection>;
+} = {}) {
+  const clients = new Map<string, LspConnection>();
+
+  async function defaultCreateConnection(input: { workspaceRoot: string; command: string[] }): Promise<LspConnection> {
+    const [command, ...args] = input.command;
+    const child = spawn(command, args, {
+      cwd: input.workspaceRoot,
+      stdio: ["pipe", "pipe", "pipe"],
+    });
+
+    const connection = rpc.createMessageConnection(
+      new rpc.StreamMessageReader(child.stdout),
+      new rpc.StreamMessageWriter(child.stdin),
+    );
+
+    let lastDiagnostics: DiagnosticsState["items"] = [];
+    connection.onNotification(PUBLISH_DIAGNOSTICS, (params: any) => {
+      lastDiagnostics = (params.diagnostics ?? []).map((diagnostic: any) => ({
+        severity: diagnostic.severity === 1 ? "error" : diagnostic.severity === 2 ? "warning" : "info",
+        message: diagnostic.message,
+        line: diagnostic.range?.start?.line !== undefined ? diagnostic.range.start.line + 1 : undefined,
+        column: diagnostic.range?.start?.character !== undefined ? diagnostic.range.start.character + 1 : undefined,
+        source: diagnostic.source ?? "lsp",
+        code: diagnostic.code ? String(diagnostic.code) : undefined,
+      }));
+    });
+
+    connection.listen();
+    await connection.sendRequest(INITIALIZE, {
+      processId: process.pid,
+      rootUri: pathToFileURL(input.workspaceRoot).href,
+      capabilities: {},
+    });
+    connection.sendNotification(INITIALIZED, {});
+
+    return {
+      async initialize() {},
+      async openTextDocument(params: any) {
+        connection.sendNotification(DID_OPEN, params);
+      },
+      async collectDiagnostics() {
+        await new Promise((resolve) => setTimeout(resolve, 100));
+        return lastDiagnostics;
+      },
+      async dispose() {
+        connection.dispose();
+        child.kill();
+      },
+    };
+  }
+
+  return {
+    async collectForFile(input: {
+      key: string;
+      absolutePath: string;
+      workspaceRoot: string;
+      languageId: string;
+      text: string;
+      command: string[];
+    }): Promise<DiagnosticsState> {
+      let client = clients.get(input.key);
+      if (!client) {
+        client = await (deps.createConnection ?? defaultCreateConnection)({
+          workspaceRoot: input.workspaceRoot,
+          command: input.command,
+        });
+        clients.set(input.key, client);
+        await client.initialize();
+      }
+
+      await client.openTextDocument({
+        textDocument: {
+          uri: pathToFileURL(input.absolutePath).href,
+          languageId: input.languageId,
+          version: 1,
+          text: input.text,
+        },
+      });
+
+      return { status: "ok", items: await client.collectDiagnostics() };
+    },
+  };
+}

.pi/agent/extensions/dev-tools/src/diagnostics/types.ts

@@ -0,0 +1,19 @@
+export interface NormalizedDiagnostic {
+  severity: "error" | "warning" | "info";
+  message: string;
+  line?: number;
+  column?: number;
+  source: string;
+  code?: string;
+}
+
+export interface DiagnosticsState {
+  status: "ok" | "unavailable";
+  items: NormalizedDiagnostic[];
+  message?: string;
+}
+
+export interface CapabilityGap {
+  path: string;
+  message: string;
+}

.pi/agent/extensions/dev-tools/src/extension.test.ts

@@ -0,0 +1,16 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import devToolsExtension from "../index.ts";
+
+test("the extension entrypoint registers edit, write, and setup suggestion tools", () => {
+  const registeredTools: string[] = [];
+
+  devToolsExtension({
+    registerTool(tool: { name: string }) {
+      registeredTools.push(tool.name);
+    },
+    on() {},
+  } as any);
+
+  assert.deepEqual(registeredTools.sort(), ["dev_tools_suggest_setup", "edit", "write"]);
+});

.pi/agent/extensions/dev-tools/src/formatting/command-runner.test.ts

@@ -0,0 +1,27 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { createCommandFormatterRunner } from "./command-runner.ts";
+
+test("formatFile expands {file} and executes in the workspace root", async () => {
+  let captured: { command: string; args: string[]; cwd?: string } | undefined;
+
+  const runner = createCommandFormatterRunner({
+    execCommand: async (command, args, options) => {
+      captured = { command, args, cwd: options.cwd };
+      return { code: 0, stdout: "", stderr: "" };
+    },
+  });
+
+  const result = await runner.formatFile({
+    absolutePath: "/repo/src/app.ts",
+    workspaceRoot: "/repo",
+    formatter: { kind: "command", command: ["biome", "format", "--write", "{file}"] },
+  });
+
+  assert.equal(result.status, "formatted");
+  assert.deepEqual(captured, {
+    command: "biome",
+    args: ["format", "--write", "/repo/src/app.ts"],
+    cwd: "/repo",
+  });
+});

.pi/agent/extensions/dev-tools/src/formatting/command-runner.ts

@@ -0,0 +1,33 @@
+import type { FormatterConfig } from "../schema.ts";
+
+export function createCommandFormatterRunner(deps: {
+  execCommand: (
+    command: string,
+    args: string[],
+    options: { cwd: string; timeout?: number },
+  ) => Promise<{ code: number; stdout: string; stderr: string }>;
+}) {
+  return {
+    async formatFile(input: {
+      absolutePath: string;
+      workspaceRoot: string;
+      formatter: FormatterConfig;
+      timeoutMs?: number;
+    }) {
+      const [command, ...args] = input.formatter.command.map((part) => part.replaceAll("{file}", input.absolutePath));
+      const result = await deps.execCommand(command, args, {
+        cwd: input.workspaceRoot,
+        timeout: input.timeoutMs,
+      });
+
+      if (result.code !== 0) {
+        return {
+          status: "failed" as const,
+          message: (result.stderr || result.stdout || `formatter exited with ${result.code}`).trim(),
+        };
+      }
+
+      return { status: "formatted" as const };
+    },
+  };
+}

.pi/agent/extensions/dev-tools/src/profiles.test.ts

@@ -0,0 +1,26 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { resolveProfileForPath } from "./profiles.ts";
+
+test("resolveProfileForPath finds the first matching profile and nearest workspace root", () => {
+  const result = resolveProfileForPath(
+    {
+      defaults: {},
+      profiles: [
+        {
+          name: "typescript",
+          match: ["src/**/*.ts"],
+          workspaceRootMarkers: ["package.json", "tsconfig.json"],
+          formatter: { kind: "command", command: ["biome", "format", "--write", "{file}"] },
+          diagnostics: [],
+        },
+      ],
+    },
+    "/repo/src/app.ts",
+    "/repo",
+    ["/repo/package.json", "/repo/src/app.ts"],
+  );
+
+  assert.equal(result?.profile.name, "typescript");
+  assert.equal(result?.workspaceRoot, "/repo");
+});

.pi/agent/extensions/dev-tools/src/profiles.ts

@@ -0,0 +1,47 @@
+import { dirname, relative, resolve } from "node:path";
+import picomatch from "picomatch";
+import type { DevToolsConfig, DevToolsProfile } from "./schema.ts";
+
+export interface ResolvedProfileMatch {
+  profile: DevToolsProfile;
+  workspaceRoot: string;
+}
+
+export function resolveProfileForPath(
+  config: DevToolsConfig,
+  absolutePath: string,
+  cwd: string,
+  knownPaths: string[] = [],
+): ResolvedProfileMatch | undefined {
+  const normalizedPath = resolve(absolutePath);
+  const relativePath = relative(cwd, normalizedPath).replace(/\\/g, "/");
+
+  for (const profile of config.profiles) {
+    if (!profile.match.some((pattern) => picomatch(pattern)(relativePath))) {
+      continue;
+    }
+
+    const workspaceRoot = findWorkspaceRoot(normalizedPath, cwd, profile.workspaceRootMarkers, knownPaths);
+    return { profile, workspaceRoot };
+  }
+
+  return undefined;
+}
+
+function findWorkspaceRoot(filePath: string, cwd: string, markers: string[], knownPaths: string[]): string {
+  let current = dirname(filePath);
+  const root = resolve(cwd);
+
+  while (current.startsWith(root)) {
+    for (const marker of markers) {
+      if (knownPaths.includes(resolve(current, marker))) {
+        return current;
+      }
+    }
+    const next = dirname(current);
+    if (next === current) break;
+    current = next;
+  }
+
+  return root;
+}

.pi/agent/extensions/dev-tools/src/project-probe.test.ts

@@ -0,0 +1,14 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { probeProject } from "./project-probe.ts";
+
+test("probeProject recognizes a TypeScript workspace and suggests biome + tsserver", async () => {
+  const result = await probeProject({
+    cwd: "/repo",
+    exists: async (path) => ["/repo/package.json", "/repo/tsconfig.json"].includes(path),
+  });
+
+  assert.equal(result.ecosystem, "typescript");
+  assert.match(result.summary, /Biome/);
+  assert.match(result.summary, /typescript-language-server/);
+});

.pi/agent/extensions/dev-tools/src/project-probe.ts

@@ -0,0 +1,68 @@
+import { access } from "node:fs/promises";
+import { resolve } from "node:path";
+
+export interface ProjectProbeResult {
+  ecosystem: string;
+  summary: string;
+}
+
+export async function probeProject(deps: {
+  cwd: string;
+  exists?: (path: string) => Promise<boolean>;
+}): Promise<ProjectProbeResult> {
+  const exists = deps.exists ?? (async (path: string) => {
+    try {
+      await access(path);
+      return true;
+    } catch {
+      return false;
+    }
+  });
+  const cwd = resolve(deps.cwd);
+
+  const hasPackageJson = await exists(resolve(cwd, "package.json"));
+  const hasTsconfig = await exists(resolve(cwd, "tsconfig.json"));
+  const hasPyproject = await exists(resolve(cwd, "pyproject.toml"));
+  const hasCargo = await exists(resolve(cwd, "Cargo.toml"));
+  const hasGoMod = await exists(resolve(cwd, "go.mod"));
+
+  if (hasPackageJson && hasTsconfig) {
+    return {
+      ecosystem: "typescript",
+      summary: "TypeScript project detected. Recommended: Biome for formatting/linting and typescript-language-server for diagnostics.",
+    };
+  }
+
+  if (hasPyproject) {
+    return {
+      ecosystem: "python",
+      summary: "Python project detected. Recommended: Ruff for formatting/linting and basedpyright or pylsp for diagnostics.",
+    };
+  }
+
+  if (hasCargo) {
+    return {
+      ecosystem: "rust",
+      summary: "Rust project detected. Recommended: rustfmt + cargo clippy and rust-analyzer.",
+    };
+  }
+
+  if (hasGoMod) {
+    return {
+      ecosystem: "go",
+      summary: "Go project detected. Recommended: gofmt/goimports and gopls.",
+    };
+  }
+
+  if (hasPackageJson) {
+    return {
+      ecosystem: "javascript",
+      summary: "JavaScript project detected. Recommended: Biome or Prettier+ESLint, plus TypeScript language tooling if applicable.",
+    };
+  }
+
+  return {
+    ecosystem: "unknown",
+    summary: "No known project toolchain markers detected. Add dev-tools profiles for your formatter, linter, and language server.",
+  };
+}

.pi/agent/extensions/dev-tools/src/runtime.test.ts

@@ -0,0 +1,44 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { createDevToolsRuntime } from "./runtime.ts";
+
+test("refreshDiagnostics falls back to command diagnostics when LSP is unavailable", async () => {
+  const runtime = createDevToolsRuntime({
+    cwd: "/repo",
+    agentDir: "/agent",
+    loadConfig: () => ({
+      defaults: { maxDiagnosticsPerFile: 5 },
+      profiles: [
+        {
+          name: "typescript",
+          match: ["src/**/*.ts"],
+          languageId: "typescript",
+          workspaceRootMarkers: ["package.json"],
+          formatter: { kind: "command", command: ["biome", "format", "--write", "{file}"] },
+          diagnostics: [
+            { kind: "lsp", command: ["typescript-language-server", "--stdio"] },
+            { kind: "command", parser: "eslint-json", command: ["eslint", "--format", "json", "{file}"] },
+          ],
+        },
+      ],
+    }),
+    knownPaths: ["/repo/package.json"],
+    formatterRunner: { formatFile: async () => ({ status: "skipped" }) },
+    lspBackend: {
+      collectForFile: async () => ({ status: "unavailable", items: [], message: "spawn ENOENT" }),
+    },
+    commandBackend: {
+      collect: async () => ({
+        status: "ok",
+        items: [{ severity: "error", message: "Unexpected console statement.", line: 2, column: 3, source: "eslint" }],
+      }),
+    },
+    probeProject: async () => ({ ecosystem: "typescript", summary: "TypeScript project detected." }),
+  });
+
+  await runtime.refreshDiagnosticsForPath("/repo/src/app.ts", "console.log('x')\n");
+
+  const promptBlock = runtime.getPromptBlock() ?? "";
+  assert.match(promptBlock, /Unexpected console statement/);
+  assert.match(promptBlock, /spawn ENOENT/);
+});

.pi/agent/extensions/dev-tools/src/runtime.ts

@@ -0,0 +1,134 @@
+import { readFile } from "node:fs/promises";
+import { loadDevToolsConfig } from "./config.ts";
+import type { CapabilityGap, DiagnosticsState } from "./diagnostics/types.ts";
+import { probeProject } from "./project-probe.ts";
+import { resolveProfileForPath } from "./profiles.ts";
+import { buildPromptBlock } from "./summary.ts";
+
+export interface FormatResult {
+  status: "formatted" | "skipped" | "failed";
+  message?: string;
+}
+
+export interface DevToolsRuntime {
+  formatAfterMutation(absolutePath: string): Promise<FormatResult>;
+  noteMutation(absolutePath: string, formatResult: FormatResult): void;
+  setDiagnostics(path: string, state: DiagnosticsState): void;
+  recordCapabilityGap(path: string, message: string): void;
+  getPromptBlock(): string | undefined;
+  refreshDiagnosticsForPath(absolutePath: string, text?: string): Promise<void>;
+}
+
+type LoadedConfig = ReturnType<typeof loadDevToolsConfig>;
+
+export function createDevToolsRuntime(deps: {
+  cwd: string;
+  agentDir: string;
+  loadConfig?: () => LoadedConfig;
+  knownPaths?: string[];
+  formatterRunner: { formatFile: (input: any) => Promise<FormatResult> };
+  lspBackend: { collectForFile: (input: any) => Promise<DiagnosticsState> };
+  commandBackend: { collect: (input: any) => Promise<DiagnosticsState> };
+  probeProject?: typeof probeProject;
+}): DevToolsRuntime {
+  const diagnosticsByFile = new Map<string, DiagnosticsState>();
+  const capabilityGaps: CapabilityGap[] = [];
+  const getConfig = () => deps.loadConfig?.() ?? loadDevToolsConfig(deps.cwd, deps.agentDir);
+
+  function setDiagnostics(path: string, state: DiagnosticsState) {
+    diagnosticsByFile.set(path, state);
+  }
+
+  function recordCapabilityGap(path: string, message: string) {
+    if (!capabilityGaps.some((gap) => gap.path === path && gap.message === message)) {
+      capabilityGaps.push({ path, message });
+    }
+  }
+
+  function getPromptBlock() {
+    const config = getConfig();
+    const maxDiagnosticsPerFile = config?.defaults?.maxDiagnosticsPerFile ?? 10;
+    if (diagnosticsByFile.size === 0 && capabilityGaps.length === 0) return undefined;
+    return buildPromptBlock({
+      maxDiagnosticsPerFile,
+      diagnosticsByFile,
+      capabilityGaps,
+    });
+  }
+
+  async function refreshDiagnosticsForPath(absolutePath: string, text?: string) {
+    const config = getConfig();
+    if (!config) {
+      recordCapabilityGap(absolutePath, "No dev-tools config found.");
+      return;
+    }
+
+    const match = resolveProfileForPath(config, absolutePath, deps.cwd, deps.knownPaths ?? []);
+    if (!match) {
+      const probe = await (deps.probeProject ?? probeProject)({ cwd: deps.cwd });
+      recordCapabilityGap(absolutePath, `No profile matched. ${probe.summary}`);
+      return;
+    }
+
+    const fileText = text ?? await readFile(absolutePath, "utf8");
+
+    for (const backend of match.profile.diagnostics) {
+      if (backend.kind === "lsp") {
+        const lspResult = await deps.lspBackend.collectForFile({
+          key: `${match.profile.languageId ?? "plain"}:${match.workspaceRoot}`,
+          absolutePath,
+          workspaceRoot: match.workspaceRoot,
+          languageId: match.profile.languageId ?? "plaintext",
+          text: fileText,
+          command: backend.command,
+        });
+
+        if (lspResult.status === "ok") {
+          setDiagnostics(absolutePath, lspResult);
+          if (lspResult.message) recordCapabilityGap(absolutePath, lspResult.message);
+          return;
+        }
+
+        recordCapabilityGap(absolutePath, lspResult.message ?? "LSP diagnostics unavailable.");
+        continue;
+      }
+
+      const commandResult = await deps.commandBackend.collect({
+        absolutePath,
+        workspaceRoot: match.workspaceRoot,
+        backend,
+        timeoutMs: config.defaults?.diagnosticTimeoutMs,
+      });
+
+      setDiagnostics(absolutePath, commandResult);
+      return;
+    }
+
+    recordCapabilityGap(absolutePath, "No diagnostics backend succeeded.");
+  }
+
+  return {
+    async formatAfterMutation(absolutePath: string) {
+      const config = getConfig();
+      if (!config) return { status: "skipped" as const };
+      const match = resolveProfileForPath(config, absolutePath, deps.cwd, deps.knownPaths ?? []);
+      if (!match?.profile.formatter) return { status: "skipped" as const };
+      return deps.formatterRunner.formatFile({
+        absolutePath,
+        workspaceRoot: match.workspaceRoot,
+        formatter: match.profile.formatter,
+        timeoutMs: config.defaults?.formatTimeoutMs,
+      });
+    },
+    noteMutation(absolutePath: string, formatResult: FormatResult) {
+      if (formatResult.status === "failed") {
+        recordCapabilityGap(absolutePath, formatResult.message ?? "Formatter failed.");
+      }
+      void refreshDiagnosticsForPath(absolutePath);
+    },
+    setDiagnostics,
+    recordCapabilityGap,
+    getPromptBlock,
+    refreshDiagnosticsForPath,
+  };
+}

.pi/agent/extensions/dev-tools/src/schema.ts

@@ -0,0 +1,40 @@
+import { Type, type Static } from "@sinclair/typebox";
+
+const CommandSchema = Type.Object({
+  kind: Type.Literal("command"),
+  command: Type.Array(Type.String({ minLength: 1 }), { minItems: 1 }),
+});
+
+const LspSchema = Type.Object({
+  kind: Type.Literal("lsp"),
+  command: Type.Array(Type.String({ minLength: 1 }), { minItems: 1 }),
+});
+
+const CommandDiagnosticsSchema = Type.Object({
+  kind: Type.Literal("command"),
+  parser: Type.String({ minLength: 1 }),
+  command: Type.Array(Type.String({ minLength: 1 }), { minItems: 1 }),
+});
+
+export const DevToolsProfileSchema = Type.Object({
+  name: Type.String({ minLength: 1 }),
+  match: Type.Array(Type.String({ minLength: 1 }), { minItems: 1 }),
+  languageId: Type.Optional(Type.String({ minLength: 1 })),
+  workspaceRootMarkers: Type.Array(Type.String({ minLength: 1 }), { minItems: 1 }),
+  formatter: Type.Optional(CommandSchema),
+  diagnostics: Type.Array(Type.Union([LspSchema, CommandDiagnosticsSchema])),
+});
+
+export const DevToolsConfigSchema = Type.Object({
+  defaults: Type.Optional(Type.Object({
+    formatTimeoutMs: Type.Optional(Type.Integer({ minimum: 1 })),
+    diagnosticTimeoutMs: Type.Optional(Type.Integer({ minimum: 1 })),
+    maxDiagnosticsPerFile: Type.Optional(Type.Integer({ minimum: 1 })),
+  })),
+  profiles: Type.Array(DevToolsProfileSchema, { minItems: 1 }),
+});
+
+export type DevToolsProfile = Static<typeof DevToolsProfileSchema>;
+export type DevToolsConfig = Static<typeof DevToolsConfigSchema>;
+export type FormatterConfig = NonNullable<DevToolsProfile["formatter"]>;
+export type DiagnosticsConfig = DevToolsProfile["diagnostics"][number];

.pi/agent/extensions/dev-tools/src/summary.test.ts

@@ -0,0 +1,27 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { buildPromptBlock } from "./summary.ts";
+
+test("buildPromptBlock caps diagnostics per file and includes capability gaps", () => {
+  const block = buildPromptBlock({
+    maxDiagnosticsPerFile: 1,
+    diagnosticsByFile: new Map([
+      [
+        "/repo/src/app.ts",
+        {
+          status: "ok",
+          items: [
+            { severity: "error", message: "Unexpected console statement.", line: 2, column: 3, source: "eslint" },
+            { severity: "warning", message: "Unused variable.", line: 4, column: 9, source: "eslint" },
+          ],
+        },
+      ],
+    ]),
+    capabilityGaps: [{ path: "/repo/src/app.ts", message: "Configured executable `eslint` not found in PATH." }],
+  });
+
+  assert.match(block, /app.ts: 1 error, 1 warning/);
+  assert.match(block, /Unexpected console statement/);
+  assert.doesNotMatch(block, /Unused variable/);
+  assert.match(block, /not found in PATH/);
+});

.pi/agent/extensions/dev-tools/src/summary.ts

@@ -0,0 +1,31 @@
+import type { CapabilityGap, DiagnosticsState } from "./diagnostics/types.ts";
+
+export function buildPromptBlock(input: {
+  maxDiagnosticsPerFile: number;
+  diagnosticsByFile: Map<string, DiagnosticsState>;
+  capabilityGaps: CapabilityGap[];
+}) {
+  const lines = ["Current changed-file diagnostics:"];
+
+  for (const [path, state] of input.diagnosticsByFile) {
+    if (state.status === "unavailable") {
+      lines.push(`- ${path}: diagnostics unavailable (${state.message ?? "unknown error"})`);
+      continue;
+    }
+
+    const errors = state.items.filter((item) => item.severity === "error");
+    const warnings = state.items.filter((item) => item.severity === "warning");
+    lines.push(`- ${path}: ${errors.length} error${errors.length === 1 ? "" : "s"}, ${warnings.length} warning${warnings.length === 1 ? "" : "s"}`);
+
+    for (const item of state.items.slice(0, input.maxDiagnosticsPerFile)) {
+      const location = item.line ? `:${item.line}${item.column ? `:${item.column}` : ""}` : "";
+      lines.push(`  - ${item.severity.toUpperCase()}${location} ${item.message}`);
+    }
+  }
+
+  for (const gap of input.capabilityGaps) {
+    lines.push(`- setup gap for ${gap.path}: ${gap.message}`);
+  }
+
+  return lines.join("\n");
+}

.pi/agent/extensions/dev-tools/src/tools/edit.test.ts

@@ -0,0 +1,54 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { mkdtemp, readFile, writeFile } from "node:fs/promises";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+import { createFormattedEditTool } from "./edit.ts";
+
+test("edit applies the replacement and then formats the file", async () => {
+  const dir = await mkdtemp(join(tmpdir(), "dev-tools-edit-"));
+  const path = join(dir, "app.ts");
+  await writeFile(path, "const x=1\n", "utf8");
+
+  const tool = createFormattedEditTool(dir, {
+    formatAfterMutation: async (absolutePath) => {
+      await writeFile(absolutePath, "const x = 2;\n", "utf8");
+      return { status: "formatted" };
+    },
+    noteMutation() {},
+  });
+
+  await tool.execute(
+    "tool-1",
+    { path, edits: [{ oldText: "const x=1", newText: "const x=2" }] },
+    undefined,
+    undefined,
+    undefined,
+  );
+
+  assert.equal(await readFile(path, "utf8"), "const x = 2;\n");
+});
+
+test("edit preserves the changed file when formatter fails", async () => {
+  const dir = await mkdtemp(join(tmpdir(), "dev-tools-edit-"));
+  const path = join(dir, "app.ts");
+  await writeFile(path, "const x=1\n", "utf8");
+
+  const tool = createFormattedEditTool(dir, {
+    formatAfterMutation: async () => ({ status: "failed", message: "formatter not found" }),
+    noteMutation() {},
+  });
+
+  await assert.rejects(
+    () => tool.execute(
+      "tool-1",
+      { path, edits: [{ oldText: "const x=1", newText: "const x=2" }] },
+      undefined,
+      undefined,
+      undefined,
+    ),
+    /Auto-format failed/,
+  );
+
+  assert.equal(await readFile(path, "utf8"), "const x=2\n");
+});

.pi/agent/extensions/dev-tools/src/tools/edit.ts

@@ -0,0 +1,21 @@
+import { createEditToolDefinition } from "@mariozechner/pi-coding-agent";
+import { constants } from "node:fs";
+import { access, readFile, writeFile } from "node:fs/promises";
+import type { DevToolsRuntime } from "../runtime.ts";
+
+export function createFormattedEditTool(cwd: string, runtime: DevToolsRuntime) {
+  return createEditToolDefinition(cwd, {
+    operations: {
+      access: (absolutePath) => access(absolutePath, constants.R_OK | constants.W_OK),
+      readFile: (absolutePath) => readFile(absolutePath),
+      writeFile: async (absolutePath, content) => {
+        await writeFile(absolutePath, content, "utf8");
+        const formatResult = await runtime.formatAfterMutation(absolutePath);
+        runtime.noteMutation(absolutePath, formatResult);
+        if (formatResult.status === "failed") {
+          throw new Error(`Auto-format failed for ${absolutePath}: ${formatResult.message}`);
+        }
+      },
+    },
+  });
+}

.pi/agent/extensions/dev-tools/src/tools/setup-suggest.test.ts

@@ -0,0 +1,15 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { createSetupSuggestTool } from "./setup-suggest.ts";
+
+test("dev_tools_suggest_setup returns a concrete recommendation string", async () => {
+  const tool = createSetupSuggestTool({
+    suggestSetup: async () => "TypeScript project detected. Recommended: bunx biome init and npm i -D typescript-language-server.",
+  });
+
+  const result = await tool.execute("tool-1", {}, undefined, undefined, undefined);
+  const text = result.content[0]?.type === "text" ? result.content[0].text : "";
+
+  assert.match(text, /TypeScript project detected/);
+  assert.match(text, /biome/);
+});

.pi/agent/extensions/dev-tools/src/tools/setup-suggest.ts

@@ -0,0 +1,17 @@
+import { Type } from "@sinclair/typebox";
+
+export function createSetupSuggestTool(deps: { suggestSetup: () => Promise<string> }) {
+  return {
+    name: "dev_tools_suggest_setup",
+    label: "Dev Tools Suggest Setup",
+    description: "Suggest formatter/linter/LSP setup for the current project.",
+    parameters: Type.Object({}),
+    async execute() {
+      const text = await deps.suggestSetup();
+      return {
+        content: [{ type: "text" as const, text }],
+        details: { suggestion: text },
+      };
+    },
+  };
+}

.pi/agent/extensions/dev-tools/src/tools/write.test.ts

@@ -0,0 +1,40 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { mkdtemp, readFile, writeFile } from "node:fs/promises";
+import { join } from "node:path";
+import { tmpdir } from "node:os";
+import { createFormattedWriteTool } from "./write.ts";
+
+test("write keeps the file when auto-format fails", async () => {
+  const dir = await mkdtemp(join(tmpdir(), "dev-tools-write-"));
+  const path = join(dir, "app.ts");
+
+  const tool = createFormattedWriteTool(dir, {
+    formatAfterMutation: async () => ({ status: "failed", message: "biome missing" }),
+    noteMutation() {},
+  });
+
+  await assert.rejects(
+    () => tool.execute("tool-1", { path, content: "const x=1\n" }, undefined, undefined, undefined),
+    /Auto-format failed/,
+  );
+
+  assert.equal(await readFile(path, "utf8"), "const x=1\n");
+});
+
+test("write calls formatting immediately after writing", async () => {
+  const dir = await mkdtemp(join(tmpdir(), "dev-tools-write-"));
+  const path = join(dir, "app.ts");
+
+  const tool = createFormattedWriteTool(dir, {
+    formatAfterMutation: async (absolutePath) => {
+      await writeFile(absolutePath, "const x = 1;\n", "utf8");
+      return { status: "formatted" };
+    },
+    noteMutation() {},
+  });
+
+  await tool.execute("tool-1", { path, content: "const x=1\n" }, undefined, undefined, undefined);
+
+  assert.equal(await readFile(path, "utf8"), "const x = 1;\n");
+});

.pi/agent/extensions/dev-tools/src/tools/write.ts

@@ -0,0 +1,23 @@
+import { createWriteToolDefinition } from "@mariozechner/pi-coding-agent";
+import { mkdir, writeFile } from "node:fs/promises";
+import { dirname } from "node:path";
+import type { DevToolsRuntime } from "../runtime.ts";
+
+export function createFormattedWriteTool(cwd: string, runtime: DevToolsRuntime) {
+  const original = createWriteToolDefinition(cwd, {
+    operations: {
+      mkdir: (dir) => mkdir(dir, { recursive: true }).then(() => {}),
+      writeFile: async (absolutePath, content) => {
+        await mkdir(dirname(absolutePath), { recursive: true });
+        await writeFile(absolutePath, content, "utf8");
+        const formatResult = await runtime.formatAfterMutation(absolutePath);
+        runtime.noteMutation(absolutePath, formatResult);
+        if (formatResult.status === "failed") {
+          throw new Error(`Auto-format failed for ${absolutePath}: ${formatResult.message}`);
+        }
+      },
+    },
+  });
+
+  return original;
+}